The Hacky Easter 2014 was a very fun CTF competition.

I decided to wrote this up because this challenge is kind of basic encode/decode that shoud help someone who want to learn or start to interesting  in computer security.

The Challenge. Hacky Easter Challenge 5 need to decode the sniffed email communication. Hacky Easter 01

When I click Download to see the encoded message it’s show as below. Hacky Easter 02

When I see encoded message, I have no idea which algorithm of this email message encoded with, then I start google to some of first character “0M8R4KGxGu” Hacky Easter 03

I am pretty sure it’s base64 encoded message. so let’s try to decode it!

I have created raw.txt which is the base64 encoded email message. then I am decode raw.txt to decoded file.

I need to determine file type so I use “file” command. It’s tell me “Composite Document File V2 Document, No summary info” Hacky Easter 04

again google answer me that it’s outlook message file(.msg) Hacky Easter 05

I copy decoded file to windows box and open with outlook. yes I found the Egg 07 attached in the email. Hacky Easter 06